Please contact me :- ajith.narayanan@infrastack-labs.in

Tuesday, December 23, 2014

I was
once contracted for a karnataka govt project linked to aadhaar for a short
period and was asked to help with a IP change for a RAC database they had, I
really did not have any clue on how to go ahead with that requirement, But
guess what? I nodded my head, indicating I could do that for them, Almost 12
hours (Morning 11AM to 11PM), I spent googling and end of the day did the IP change
for them. But if you ask me how I did that, Sorry no idea. So that led me to
write a step-by-step sequence of activities for changing the IP’s of a RAC
database.

On what scenario do you need a
IP change for your DB servers?

One of
the PCI audit requirements is that any database that holds any payment card
details should be placed in an isolated network seperated behind special
firewalls. In such scenario the we may need to to change the IP address of the
database server matching to the new datacenter public network. In this article,
I would like explain the step by step approach to change your database node IP
in a steamlined manner.

Ideally
each of our database servers are having 3 IP addresses.

·

Public
IP – resolving to the name e.g. ajithpathiyil1. This is
recorded in DNS and the /etc/hosts file.

·

Virtual
IP (VIP)– resolving to the name -vip e.g.
ajiithpathiyil1-vip. This is recorded in DNS and the /etc/hosts file.

·

Private
Interconnect IP – resolving to the name -priv. e.g.
ajithpathiyil1-priv. This only exists in the /etc/hosts file on each server in
the cluster, as these as they are on a private interconnect network local only
to the servers.

Only the public and VIP IP addresses are changing,
as the private network isn’t on the LAN, and so no other systems or servers can
access it.

The following table shows the old and new IP
addresses, I want to change:

(Note for this demo, I will be using the IP
address within my home network, But the procedure remains same for IP’s that
will belong to different networks as well)

15.Review the /etc/hosts file. The setif command
above might have appended an entry for the server to the hosts file, pointing
to the private interconnect IP. If it has, remove it. In addition, check that
the entry for the public IP has the servername with the FQDN, as well as just a
servername entry (i.e. lab.com in my case).

16.Change the VIP IP address in CRS as root
(correcting the servername, IP address and subnet mask as appropriate):

Sunday, December 21, 2014

If you are planning
for a R12.2 upgrade, To get initial idea on how much of work is required for
standard & custom remediation and making it online patching compliant, we
can start with upgrade readiness patch and API's